There is a certain logic in extending the gable overhang further the higher you get as you mention but that complicates the roof and i don t like the look of it.
Roof overhang minimum.
The edge of the shingles should hang over the edge of the roof between an inch and an inch and a half or between a half inch and three quarters of an inch if drip edge flashing is installed and in most cases it should be.
Browse 295 roof overhang on houzz whether you want inspiration for planning roof overhang or are building designer roof overhang from scratch houzz has 295 pictures from the best designers decorators and architects in the country including dodge construction llc and bergerson tile cabinets.
Roof overhangs can extend farther than 2 feet but beyond this length they begin to lose structural integrity and require external supports.
Figure r804 3 2 1 2 gable endwall overhang details.
However you can only use this pitch with built up roofing or specialized synthetic roofing.
For the south side of the home you should follow basic solar design principles.
This will protect a roof from most types of damage.
The roof overhang will be 36 inches at the eaves measured horizontally and 36 inches at the gable ends.
Anything else is down to design but the more the better.
When constructing a roof framework the rule of thumb is that any purlin should have a minimum nominal depth and width of 76 mm or 50 mm and max centre to centre spacing between the purlins ought to be 1 2 m.
Knowledgeable roofers will install shingles at just the right overhang for your roof type.
The minimum is 50mm to allow for a drip.
Joints between purlins next to one another should be staggered.
But the tables that follow are a lot more specific.
The minimum pitch for a roof is 1 4 12 which translates to 1 4 inch rise to 12 inches of run.
A typical metal roof overhang may be 2 to 4 inches or even less.
In short that means that the roof overhang should be of sufficient dimensions to optimize the amount of shade during the warm summer months but not be so large that they do not allow full sun exposure during the cold winter months.
Eave overhangs shall not exceed 24 inches 610 mm measured horizontally.
Some slight overhang is recommended in conjunction with a drip edge flashing to prevent water from getting under the roofing and onto underlying wood.
Metal is usually installed on rafters or strip sheathing rather than the solid decking used under other materials.
This can make extensive roof overhangs more trouble than they are worth in all but the harshest climates.